Features of interest:
Allow setting target local variables (similar to gmake)
In META_MODE .MAKE.META.CMP_FILTER can be used for filtering commands
before comparion.
contrib/bmake/mk/cc-wrap.mk is an example of using these
See ChangeLog for the gory details.
Lots of code refactoring, simplification and cleanup.
Lots of new unit-tests providing much higher code coverage.
All courtesy of rillig at netbsd.
Other significant changes:
o new read-only variable .SHELL which provides the path of the shell
used to run scripts (as defined by the .SHELL target).
o new debug option -dl: LINT mode, does the equivalent of := for all
variable assignments so that file and line number are reported for
variable parse errors.